Automotive carburetors or throttle bodies usually have a throttle valve which is manually (by hand or by foot) actuated to control the speed of an engine. This throttle valve controls either the air and fuel mixture in a mixing passage of a carburetor or the air flow through a throttle body in fuel systems where the fuel is injected into a manifold or into individual cylinders.
In either case, it is a requirement that a double spring be utilized to bring the throttle valve to a closed position when the manual control is released or in the exceptional circumstance when a throttle control linkage becomes disconnected or fails for any reason. The reason for the double coil requirement lies in the desire to have at least one spring operating to close the throttle in the event the other spring fails for some reason.
It is an object of the present invention to provide a double coil spring assembly which meets the standards requirement.
It is a further object to provide a one-piece bushing assembly to carry both springs which is inexpensive to manufacture and which provides an assembly unit which can be handled as a single component and readily assembled to its final position on the throttle shaft which it is intended to control.
It is a further object to provide an assembly which occupies a minimum of space and in which the spring legs all anchor on a solid material other than the integral spool.
Other objects and features of the invention will be apparent in the following description and claims in which the invention is described, together with details to enable persons skilled in the art to practice the invention, all in connection with the best mode presently contemplated for the invention.